/**
 * Given a string S and a string T, find the minimum window in S which will contain all the characters in T in complexity O(n).
 * For example,S = "ADOBECODEBANC"
 * T = "ABC"
 * Minimum window is "BANC".Note:
 * If there is no such window in S that covers all characters in T, return the empty string "".
 * If there are multiple such windows, you are guaranteed that there will always be only one unique minimum window in S.
 */
/**
 * @author Ivan
 *
 */
package problem76_Minimum_Window_Substring;